﻿/**
* @author trixta
* @version 1.2
*/
(function ($) {

  var mwheelI = {
    pos: [-260, -260]
  },
	minDif = 3,
	doc = document,
	root = doc.documentElement,
	body = doc.body,
	longDelay, shortDelay
;

  function unsetPos() {
    if (this === mwheelI.elem) {
      mwheelI.pos = [-260, -260];
      mwheelI.elem = false;
      minDif = 3;
    }
  }

  $.event.special.mwheelIntent = {
    setup: function () {
      var jElm = $(this).bind('mousewheel', $.event.special.mwheelIntent.handler);
      if (this !== doc && this !== root && this !== body) {
        jElm.bind('mouseleave', unsetPos);
      }
      jElm = null;
      return true;
    },
    teardown: function () {
      $(this)
			.unbind('mousewheel', $.event.special.mwheelIntent.handler)
			.unbind('mouseleave', unsetPos)
		;
      return true;
    },
    handler: function (e, d) {
      var pos = [e.clientX, e.clientY];
      if (this === mwheelI.elem || Math.abs(mwheelI.pos[0] - pos[0]) > minDif || Math.abs(mwheelI.pos[1] - pos[1]) > minDif) {
        mwheelI.elem = this;
        mwheelI.pos = pos;
        minDif = 250;

        clearTimeout(shortDelay);
        shortDelay = setTimeout(function () {
          minDif = 10;
        }, 200);
        clearTimeout(longDelay);
        longDelay = setTimeout(function () {
          minDif = 3;
        }, 1500);
        e = $.extend({}, e, { type: 'mwheelIntent' });
        return $.event.handle.apply(this, arguments);
      }
    }
  };
  $.fn.extend({
    mwheelIntent: function (fn) {
      return fn ? this.bind("mwheelIntent", fn) : this.trigger("mwheelIntent");
    },

    unmwheelIntent: function (fn) {
      return this.unbind("mwheelIntent", fn);
    }
  });

  $(function () {
    body = doc.body;
    //assume that document is always scrollable, doesn't hurt if not
    $(doc).bind('mwheelIntent.mwheelIntentDefault', $.noop);
  });
})(jQuery);